The prime minister’s speech yesterday was a well-meaning attempt to strike a reasonable note on the perennial hot topic of crime, but it was one which failed to satisfy either the ‘bang ‘em up’ brigade or those who champion significant penal reform.

The reaction of the former group might best be understood from this opinion piece by Daily Express political editor Patrick O’Flynn.

On this reading, the prime minister’s ‘tough but intelligent’ slogan is troubling because it suggests simply being tough is unintelligent. Yet for the public surely what matters is not whether a policy might be characterised as ‘tough’ or ‘soft’ but rather whether it is effective.

On this, Mr O’Flynn suggests the doubling of the prison population since the mid-1990s has been behind sustained falls in recorded crime. This correlation is misleading, however, not least because in our own history and in other jurisdictions, there are counter examples of periods when both prison numbers and crime levels fell.

A report commissioned by Tony Blair, himself no shrinking violet on the use of imprisonment, found only a sixth of the fall in crime since the late 1990s could be attributed to a 22 per cent rise in prison places. The real drivers in reducing ‘bulk’ crime (i.e. burglary and other acquisitive offences) were the booming economy, improvements in home security and a fall in the secondhand price of electronic goods.

Mr O’Flynn also looks at the reoffending rates of different lengths of prison sentence and points out longer prison sentences have lower reoffending rates than short prison sentences. However, those serving many years in prison for very serious offences are more often than not quite different people than those who are in and out of custody on minor offences.

It is also no surprise those serving sentences of 10 years or more have the lowest reoffending rates, as it is likely that in the passing of a decade an individual has simply matured. Young men for example are more likely to commit violent crimes than middle aged men. It is not the incarceration itself that is the agent of change here.

It is more instructive to compare like with like, looking at those on short prison sentences of under 12 months alongside those serving community sentences for similar offences. There we find community sentences are more effective at reducing reoffending rates by eight percentage points. Moreover, those discharged from custody are not only more likely to reoffend but are more likely to reoffend multiple times.

The reoffending rate also increases exponentially after each spell in prison.

If we were to follow the logic of the Daily Express and bang everyone up for longer, then we would swiftly end up in a situation akin to that of the United States, where huge swaths of the population are either in prison or on supervision in the community. There, individual states have been literally bankrupted by their spending on prison and are now desperately embracing penal reform. This includes figures on the right such as Newt Gingrich and Grover Norquist.

Yet the prime minister’s approach is also troubling. Unwilling to make a bold case for sentencing reform that would reduce prison numbers, focusing on effective community interventions and a better use of scarce resources within prison walls, David Cameron has put a great deal of store in the policy of payment by results. Here I would agree with Mr O’Flynn that the government is in danger of overhyping this untested approach.

It is all very well to pay providers by results but you must have a result that is meaningful in the first place. The Ministry of Justice is looking at paying providers on whether individuals are reconvicted or not but this is a blunt measure that does not reflect the reality of how people desist from crime.

Rather than simply shift from offending to not offending like an electrical switch, people who offend tend to lead chaotic lives and slip in and out of trouble with the law.

Sometimes progress is better measured in whether people are reoffending less seriously or less frequently than before. That kind of progress would not be measured under current proposals, which raises questions as to what success any providers will be able to produce.

We may well find providers resort to cherry-picking the easy cases in order to meet their targets. Yet focusing resources on people who are less likely to reoffend anyway would make a mockery of the whole policy.

There is also a more worrying proposal that the prime minister mentioned yesterday and which will be tabled today in the Crime and Courts Bill. The government plans to introduce mandatory punitive elements into every community order, such as fines, curfews and unpaid work. Removing the discretion of professionals to tailor community orders around an individual’s circumstances is a grave mistake.

Indeed, the Ministry of Justice’s own impact assessment for this policy admits that inserting a punitive element into every community order means removing a rehabilitative element, otherwise the order would cost more to deliver. In the age of austerity, this is not an option.

As the Ministry of Justice admits in bland yet revealing language:

“Some of the rehabilitative benefits of current community orders could be lost with adverse implications for the reoffending rates of those offenders subject to community orders.”

In other words, the prime minister may be scuppering his rehabilitation revolution before it has even started.

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